Date   
Re: Computer screen such as in video #sdrsharp

Tudor Vedeanu
 

On Fri, Apr 27, 2018 at 04:43 pm, EB4APL wrote:

On the top right there is an analog meter. It is from some plugin, but which one?

The Toolbar plugin: https://sdrplugins.com/toolbar-plugin

Re: Computer screen such as in video #sdrsharp

EB4APL
 

Well, I see two "specials":

- On the top right there is an analog meter. It is from some plugin, but which one?

- The top IF spectrum is from another plugin, the IF processor from Vassili

73 de Ignacio, EB4APL



El 27/04/2018 a las 23:11, h. garcia escribió:
Luciano,

Nothing special there. Just find signals between 250-260MHz using an external antenna, use FM narrow and you will be good.

PT_br: nada especial, apenas procure sinais entre 250-260MHz com antena externa, use o modo Narrow FM e você deverá receber os sinais.

On Fri, Apr 27, 2018, 11:50 PT9KK via Groups.Io <luciano_nachif=yahoo.com@groups.io> wrote:
Could someone explain me how to set up my SDR# such as in this video, please?
https://youtu.be/_y45cQ_W6yQ

73,

Luciano Gasparini


locked Re: "USB noise" and Re: HF+ SMA nut warning!!!

jdow
 

I believe I have mentioned the informal testing I made when I hooked up the HF+ to my newly acquired 8664A signal generator. A really short all connector adaptor connection to the 8664A and some serious ferrite on the USB cable made a reduction in eSmog pickup. KFI was my first clue to the fact that the noise I was still seeing was really "signal" that had not been more thoroughly attenuated to keep it out of the box. I note that a 4' RG8U cable between 8664A and HF+ made a nice antenna. Removing it reduced a lot of the discrete noise I was seeing.

After a moment's playing with Google Earth Pro, in terms of population density which correlates nicely with RF noise density, the Greater Los Angles area is over 7000 square km crammed full if "market" for broadcast advertisers in a spectrum that has remarkably few pirate radio stations chiefly because they have no place to fit into. It's electronics hell. Make a small 9" circumference loop out of a 450 MHz analog scope's 10:1 probe and it's ground clip. At its highest sensitivity setting you CANNOT make the trace look like it is properly focused because of all the RF it picks up.

Two kinds of radios do not show unwanted signal pickup with the kind of hookup I used for testing the HF+, Broken/numb or build like a battleship. Heck, we even used one of the earlier HP spectrum analyzers as a TV set using a scope probe antenna and clever settings on the controls to give a recognizable picture. Every RF lab I worked in featured one or another type of shield room for serious testing. A double wall of copper welded screen (<1mm squares) is "OK". The best room I worked in was annoyingly warm in use. It was made with a double layer of sheet copper. And even that was not dead quiet. It was quiet enough to be used, though.

No matter how good you make something some annoying bitch will come along and declare it is not good enough for what she wants. Heck, all I am saying is that it's not perfect; but, it's likely to be good enough for any real uses. All the shielding I did merely reduced signals that would come in the antenna anyway. I'm sorry, I just have a button that gets pushed when I am fed an absolutist statement that X cannot be done or Y is never going to be needed. My brain almost instantly provides that worst case. The only case I can see that might benefit from extra shielding would be the RPi "USB noise" case, which is merely conducted in on the USB cable and isn't USB noise per se.

{o.o}

On 20180427 15:52, prog wrote:
On Fri, Apr 27, 2018 at 03:49 pm, jdow wrote:
By now it should occur to somebody that the problem seen by RPi users with
noise suggest that the internal Faraday Cage around the sensitive
electronics is good but in some extreme cases not good enough.
(Over)tightening the SMA connector's mounting nut has the lockwasher poking
holes in the paint down to metal chassis. That is why I simply made it
easier by using a (sacrificial) knife blade held nearly perpendicular to the
surface as a scraping tool to remove paint.
Do you happen to test things before speculating?

locked Re: "USB noise" and Re: HF+ SMA nut warning!!!

jdow
 

Did and done. When I tested with the 8664A I have acquired (cheap and decidedly not up to spec all the way) I had to use a short string of adapters from the 8664 to the HF+ input to cut down noise. That made a difference. Then I wrapped the USB cable, gently, three turns and put it in a large clamp-on ferrite bead. That, too, reduced noise - much of which, I note, I traced to "local" high power AM broadcast stations. (The Los Angeles area is like a high power comb generator on the AM broadcast band.) Note, I said reduced not eliminated. I suspect that if I played some grounding tricks with the HF+ chassis I might see another reduction but not elimination of noise pickup.

I think it was Urgh the Caveman (Ugh's older brother) who first observed , referring to the existence of his stereotypical mother-in-law, "Nothing is ever perfect." He's still correct.

I am emphatically not saying HF+ is bad. I am saying more careful custom (quite expensive if performed in production) TLC spent on reducing noise may show a quite worthwhile improvement.

I will further note that since about 1960 I do not think I have ever run a piece of ham gear for very long without "improving it". I am gratified that the scare quotes are not really needed in most cases. So far I have not modified the HF+ as for most of my recent efforts it is "good enough." And I remember that "Perfect" is the mortal enemy of "good enough."

{^_^}

On 20180427 11:58, prog wrote:
On Fri, Apr 27, 2018 at 11:51 am, Leif Asbrink wrote:
As you could see in my video "HF+ as a power meter"
I had a real problem at 100 kHz which was fixed by better contact
between the SMA connector and the box.
I have the impression the SMA connector was broken before that test and fastening it to the enclosure made a better contact to the ground. The easiest way to validate this is to apply some common mode current to the naked PCB, between the SMA connector and the USB and see what happens.

locked Re: "USB noise" and Re: HF+ SMA nut warning!!!

prog
 

On Fri, Apr 27, 2018 at 12:06 pm, Chris Smolinski wrote:
I was curious what I would see, so I performed the above test here. No change in the backgruond noise level was noted. I checked, the SMA connector nut on my AirSpyHF+ seems tight as-is from the factory.

Chris Smolinski
Black Cat Systems
Westminster, MD USA
http://www.blackcatsystems.com
Thanks for confirming. There are two main goals behind this design:
  1. Avoid depending on the quality of the enclosure assembly,
  2. Delegate all the interference mitigation to the end user in a transparent way: We won't fix your common mode current problems.
Both were achieved using a careful PCB and RF shield design. Unless one actually breaks a connector, there's very little chance common mode current will pass to the tuner.

locked Re: "USB noise" and Re: HF+ SMA nut warning!!!

prog
 

On Fri, Apr 27, 2018 at 03:49 pm, jdow wrote:
By now it should occur to somebody that the problem seen by RPi users with noise suggest that the internal Faraday Cage around the sensitive electronics is good but in some extreme cases not good enough. (Over)tightening the SMA connector's mounting nut has the lockwasher poking holes in the paint down to metal chassis. That is why I simply made it easier by using a (sacrificial) knife blade held nearly perpendicular to the surface as a scraping tool to remove paint.
Do you happen to test things before speculating?

locked Re: "USB noise" and Re: HF+ SMA nut warning!!!

jdow
 

By now it should occur to somebody that the problem seen by RPi users with noise suggest that the internal Faraday Cage around the sensitive electronics is good but in some extreme cases not good enough. (Over)tightening the SMA connector's mounting nut has the lockwasher poking holes in the paint down to metal chassis. That is why I simply made it easier by using a (sacrificial) knife blade held nearly perpendicular to the surface as a scraping tool to remove paint.

Note also that the SMA connector is not the only way eSmog can get into the case. The SMA connector is another candidate. Some very fine braid making a compression fit out of the scraped out SMA connector's hole in the chassis gives you a better noise power divider. Increase common mode cable impedance with ferrites. Decrease common mode input impedance with a good ground. Either one alone is good. Both together is better.

{^_^}

On 20180427 11:51, Leif Asbrink wrote:
Hi Yussef,

These radios have different rf shielding constraints and
strategies. Most of the pickup happens at the impedance
matching stage, which is inside a metal can for the HF+.
As you could see in my video "HF+ as a power meter"
I had a real problem at 100 kHz which was fixed by better contact
between the SMA connector and the box.
https://www.youtube.com/watch?v=ipwWayemCSQ
Before doing the video I had already tightened the nuts
somewhat because in the original shape they were VERY
loose.
There is a very simple test as you can see in the video.
Connect a dummy load or just leave the input unconnected.
Then hold the screen of your antenna cable in contact
with the SMA connector. If you see no interference,
all is fine.
In case you see interference, hold the screen of your
antenna cable in contact with one of the screws that
hold the lid of the box. It then there is no interference
or much less interference you need to do something.
Alternatives:
1) Just tighten the SMA nut, but be careful, not hard.
2) Remove the surface coating on the box around the SMA
conector. Then #1.
3) Put appropriate washers on the inside so you can
safely tighten the nut properly. Maybe also #2.
4) Unsolder the SMA connectors and solder them back
when tightened with the card inside the box.
Maybe also #2.
5) Insert an isolation transformer in the antenna cable
to make common mode currents smaller.
6) Put ferrites on the antenna cable to make common
mode currents smaller.
7) Put ferrites on the USB cable to make common mode
currents smaller.
8) Run the antenna cable via the computer and connect
the screen to a ground point near the USB connector
You can combine #5 to #8
With the HF+ any of #1 to #4 should be sufficient.
With other SDRs like Airspy 1 you can do something
corresponding to #1 to #4 as described here:
https://www.youtube.com/watch?v=fXGMEdeGkbg
and here:
https://www.youtube.com/watch?v=cAuNwE69jes
For FunCube, rtlsdr and others you need #5 to #8.
Note that the above is about common mode currents
entering a radio receiver. For these tests the center
conductor is not used.
About ferrites:
https://www.youtube.com/watch?v=RwmjjxZoVac
https://www.youtube.com/watch?v=-mCRLfUnXTE
Another problem is how to isolate the antenna feedpoint
from currents coming along the coax from the schack.
The antenna cable picks up the electrosmog of your house
and sends it along the cable. The cable has to be
grounded well outside the electrosmog and only if you
have a near perfect ground it will be enough to
use the antenna ground. Typically you also need
an isolation transformer outside the electrosmog also.
By use of more than one ground point and more than
one isolator, very simple groundpoints are adequete.
For electrosmog and antenna isolation, look here:
http://www.youtube.com/watch?v=ItLkn8r4s3E
http://www.youtube.com/watch?v=zsZTX7MQSGQ
http://www.youtube.com/watch?v=kgMbaJDFu9M
http://www.youtube.com/watch?v=C65u7Pmz7a0
73
Leif

On Fri, Apr 27, 2018 at 03:32 am, jdow wrote:


That's why I specified the AirSpy R1 a couple times. And I have a
suspicion that in noisy environments with demonstrable pickup issues
keeping noise outside the box as well as outside the shielded compartment
would be a good thing.

{^_^}
These radios have different rf shielding constraints and strategies. Most of the pickup happens at the impedance matching stage, which is inside a metal can for the HF+.

locked Re: Which wideband SDR now?

jdow
 

If you mean broadcast FM DXing aren't you forgetting the HF+? If you mean taxi, police, etc NFM radio outside the HF+'s range, qood question.

{^_^}

On 20180427 07:13, Paul wrote:
With the demise of the R820T and Airspy are there any new products in the pipeline or do we start looking at the alternatives for FM broadcast DXing?
The SDRPlay RSP1A looks like the closest competition before the price jumps up to something like an Elad S2 especially if the new S3 ever makes it to the market but I'd prefer something that works in SDR# due to the amount of useful plugins available. Asking because I have the opportunity to put in a remote station but don't have a spare Airspy.

Re: Computer screen such as in video #sdrsharp

h. garcia
 

Luciano,

Nothing special there. Just find signals between 250-260MHz using an external antenna, use FM narrow and you will be good.

PT_br: nada especial, apenas procure sinais entre 250-260MHz com antena externa, use o modo Narrow FM e você deverá receber os sinais.

On Fri, Apr 27, 2018, 11:50 PT9KK via Groups.Io <luciano_nachif=yahoo.com@groups.io> wrote:
Could someone explain me how to set up my SDR# such as in this video, please?
https://youtu.be/_y45cQ_W6yQ

73,

Luciano Gasparini

locked Re: "USB noise" and Re: HF+ SMA nut warning!!!

Herbert
 

Hi all,

please keep an eye on the fact, that after fastende comes
..... broken !

Especialy SMA connectors should only be really fastend with
a torque wrench !

Herbert



Am 27.04.2018 20:06, schrieb Chris Smolinski:

On Apr 27, 2018, at 2:51 PM, Leif Asbrink <leif@...> wrote:

Hi Yussef,

These radios have different rf shielding constraints and
strategies. Most of the pickup happens at the impedance
matching stage, which is inside a metal can for the HF+.
As you could see in my video "HF+ as a power meter"
I had a real problem at 100 kHz which was fixed by better contact
between the SMA connector and the box.
https://www.youtube.com/watch?v=ipwWayemCSQ

Before doing the video I had already tightened the nuts
somewhat because in the original shape they were VERY
loose.

There is a very simple test as you can see in the video.
Connect a dummy load or just leave the input unconnected.

Then hold the screen of your antenna cable in contact
with the SMA connector. If you see no interference,
all is fine.
I was curious what I would see, so I performed the above test here. No change in the backgruond noise level was noted. I checked, the SMA connector nut on my AirSpyHF+ seems tight as-is from the factory.

Chris Smolinski
Black Cat Systems
Westminster, MD USA
http://www.blackcatsystems.com




locked Re: "USB noise" and Re: HF+ SMA nut warning!!!

Chris Smolinski
 

On Apr 27, 2018, at 2:51 PM, Leif Asbrink <leif@...> wrote:

Hi Yussef,

These radios have different rf shielding constraints and
strategies. Most of the pickup happens at the impedance
matching stage, which is inside a metal can for the HF+.
As you could see in my video "HF+ as a power meter"
I had a real problem at 100 kHz which was fixed by better contact
between the SMA connector and the box.
https://www.youtube.com/watch?v=ipwWayemCSQ

Before doing the video I had already tightened the nuts
somewhat because in the original shape they were VERY
loose.

There is a very simple test as you can see in the video.
Connect a dummy load or just leave the input unconnected.

Then hold the screen of your antenna cable in contact
with the SMA connector. If you see no interference,
all is fine.
I was curious what I would see, so I performed the above test here. No change in the backgruond noise level was noted. I checked, the SMA connector nut on my AirSpyHF+ seems tight as-is from the factory.

Chris Smolinski
Black Cat Systems
Westminster, MD USA
http://www.blackcatsystems.com

locked Re: "USB noise" and Re: HF+ SMA nut warning!!!

prog
 

On Fri, Apr 27, 2018 at 11:51 am, Leif Asbrink wrote:
As you could see in my video "HF+ as a power meter"
I had a real problem at 100 kHz which was fixed by better contact
between the SMA connector and the box.
I have the impression the SMA connector was broken before that test and fastening it to the enclosure made a better contact to the ground. The easiest way to validate this is to apply some common mode current to the naked PCB, between the SMA connector and the USB and see what happens.

locked "USB noise" and Re: HF+ SMA nut warning!!!

Leif Asbrink
 

Hi Yussef,

These radios have different rf shielding constraints and
strategies. Most of the pickup happens at the impedance
matching stage, which is inside a metal can for the HF+.
As you could see in my video "HF+ as a power meter"
I had a real problem at 100 kHz which was fixed by better contact
between the SMA connector and the box.
https://www.youtube.com/watch?v=ipwWayemCSQ

Before doing the video I had already tightened the nuts
somewhat because in the original shape they were VERY
loose.

There is a very simple test as you can see in the video.
Connect a dummy load or just leave the input unconnected.

Then hold the screen of your antenna cable in contact
with the SMA connector. If you see no interference,
all is fine.

In case you see interference, hold the screen of your
antenna cable in contact with one of the screws that
hold the lid of the box. It then there is no interference
or much less interference you need to do something.

Alternatives:

1) Just tighten the SMA nut, but be careful, not hard.
2) Remove the surface coating on the box around the SMA
conector. Then #1.
3) Put appropriate washers on the inside so you can
safely tighten the nut properly. Maybe also #2.
4) Unsolder the SMA connectors and solder them back
when tightened with the card inside the box.
Maybe also #2.
5) Insert an isolation transformer in the antenna cable
to make common mode currents smaller.
6) Put ferrites on the antenna cable to make common
mode currents smaller.
7) Put ferrites on the USB cable to make common mode
currents smaller.
8) Run the antenna cable via the computer and connect
the screen to a ground point near the USB connector

You can combine #5 to #8

With the HF+ any of #1 to #4 should be sufficient.
With other SDRs like Airspy 1 you can do something
corresponding to #1 to #4 as described here:
https://www.youtube.com/watch?v=fXGMEdeGkbg
and here:
https://www.youtube.com/watch?v=cAuNwE69jes

For FunCube, rtlsdr and others you need #5 to #8.

Note that the above is about common mode currents
entering a radio receiver. For these tests the center
conductor is not used.
About ferrites:
https://www.youtube.com/watch?v=RwmjjxZoVac

https://www.youtube.com/watch?v=-mCRLfUnXTE


Another problem is how to isolate the antenna feedpoint
from currents coming along the coax from the schack.

The antenna cable picks up the electrosmog of your house
and sends it along the cable. The cable has to be
grounded well outside the electrosmog and only if you
have a near perfect ground it will be enough to
use the antenna ground. Typically you also need
an isolation transformer outside the electrosmog also.

By use of more than one ground point and more than
one isolator, very simple groundpoints are adequete.
For electrosmog and antenna isolation, look here:
http://www.youtube.com/watch?v=ItLkn8r4s3E

http://www.youtube.com/watch?v=zsZTX7MQSGQ

http://www.youtube.com/watch?v=kgMbaJDFu9M

http://www.youtube.com/watch?v=C65u7Pmz7a0


73

Leif








On Fri, Apr 27, 2018 at 03:32 am, jdow wrote:


That's why I specified the AirSpy R1 a couple times. And I have a
suspicion that in noisy environments with demonstrable pickup issues
keeping noise outside the box as well as outside the shielded compartment
would be a good thing.

{^_^}
These radios have different rf shielding constraints and strategies. Most of the pickup happens at the impedance matching stage, which is inside a metal can for the HF+.

locked Re: Which wideband SDR now?

prog
 

On Fri, Apr 27, 2018 at 09:04 am, Chris Smolinski wrote:
Good to hear! Hopefully that can be achieved via component value changes. I'm certainly interested :)

Chris Smolinski
Black Cat Systems
Westminster, MD USA
http://www.blackcatsystems.com
Also some firmware modifications. Basically, we are working so more units pass the QA tests instead of loosening the tests scripts.

locked Re: Which wideband SDR now?

Chris Smolinski
 

On Apr 27, 2018, at 12:01 PM, prog <@prog> wrote:

On Fri, Apr 27, 2018 at 08:36 am, Joe M. wrote:
Per previous posts from March, the Airspy R2
is being redesigned to use a newer chip

Joe M.
Correct. Meanwhile, we are investigating with Rafael how to adapt the BOM to get the nominal performance we used to have with older batches.
Stay tuned.
_._,_._,_
Good to hear! Hopefully that can be achieved via component value changes. I'm certainly interested :)

Chris Smolinski
Black Cat Systems
Westminster, MD USA
http://www.blackcatsystems.com

locked Re: Which wideband SDR now?

prog
 

On Fri, Apr 27, 2018 at 08:36 am, Joe M. wrote:
Per previous posts from March, the Airspy R2
is being redesigned to use a newer chip

Joe M.
Correct. Meanwhile, we are investigating with Rafael how to adapt the BOM to get the nominal performance we used to have with older batches.
Stay tuned.

locked Re: Which wideband SDR now?

Joe M.
 

Per previous posts from March, the Airspy R2
is being redesigned to use a newer chip

Joe M.

Am 27.04.2018 um 14:13 schrieb Paul:
With the demise of the R820T and Airspy are there any new products in
the pipeline or do we start looking at the alternatives for FM
broadcast DXing?

Computer screen such as in video #sdrsharp

PT9KK
 

Could someone explain me how to set up my SDR# such as in this video, please?
https://youtu.be/_y45cQ_W6yQ

73,

Luciano Gasparini

locked Re: Which wideband SDR now?

Shirley Dulcey KE1L
 

The Airspy HF+ should work fine for FM broadcast DXing, and it's still
available. But it's not suitable for listening to UHF mobile radio or
other things happening above 260 MHz, or in the gap between 31 MHz and
60 MHz.

Cheap RTL dongles are still available for now, but the supply will
presumably dry up once the supply of R820T2 tuners runs out.

On Fri, Apr 27, 2018 at 10:13 AM, Paul <aceblaggard@...> wrote:
With the demise of the R820T and Airspy are there any new products in the
pipeline or do we start looking at the alternatives for FM broadcast DXing?

The SDRPlay RSP1A looks like the closest competition before the price jumps
up to something like an Elad S2 especially if the new S3 ever makes it to
the market but I'd prefer something that works in SDR# due to the amount of
useful plugins available. Asking because I have the opportunity to put in a
remote station but don't have a spare Airspy.

locked Re: Which wideband SDR now?

Siegfried Jackstien
 

hmmm ... lime, lime mini, adalm pluto, ... and the new xtrx

all should have enough bw for the complete fm band

dg9bfc sigi


Am 27.04.2018 um 14:13 schrieb Paul:

With the demise of the R820T and Airspy are there any new products in the pipeline or do we start looking at the alternatives for FM broadcast DXing?

The SDRPlay RSP1A looks like the closest competition before the price jumps up to something like an Elad S2 especially if the new S3 ever makes it to the market but I'd prefer something that works in SDR# due to the amount of useful plugins available. Asking because I have the opportunity to put in a remote station but don't have a spare Airspy.